20695399 has 2 divisors, whose sum is σ = 20695400. Its totient is φ = 20695398.

The previous prime is 20695397. The next prime is 20695453. The reversal of 20695399 is 99359602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20695399 - 2¹ = 20695397 is a prime.

Together with 20695397, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20695391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10347699 + 10347700.

It is an arithmetic number, because the mean of its divisors is an integer number (10347700).

Almost surely, 2^20695399 is an apocalyptic number.

20695399 is a deficient number, since it is larger than the sum of its proper divisors (1).

20695399 is an equidigital number, since it uses as much as digits as its factorization.

20695399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 131220, while the sum is 43.

The square root of 20695399 is about 4549.2196034045. The cubic root of 20695399 is about 274.5519934071.

The spelling of 20695399 in words is "twenty million, six hundred ninety-five thousand, three hundred ninety-nine".